The present invention relates to a brake apparatus for use in a vehicle and more particularly to a control system for a vehicular brake apparatus that does not utilize fluid pressure such as hydraulic pressure or air pressure.
In conventional brake apparatuses for a vehicle, for example drum brake and disc brake apparatuses, fluid pressure generated by depressing a brake pedal is boosted by a booster device and transmitted to a brake apparatus through hydraulic pressure lines to actuate the brake.
In conventional brake apparatuses of this type, loss of pressure transmitted through the lines is relatively large, and thus efficiency of the brake apparatus has been less than satisfactory. Further, locations for the components are limited because the brake lines require significant space.
Furthermore, in the conventional brake apparatus, since the braking force is achieved only by a frictional force between a braked member such as a rotor and a friction material such as a pad, considerable noise due to drag is generated during the braking operation, and the fade phenomenon, which is a serious problem, sets in if the braking operation continues for a long time. Moreover, when an auxiliary brake system, such as an anti-lock control system or traction control system is employed, an extra actuator is required so that not only the number of components increases, but also manufacturing cost.
Moreover, since control of braking force is determined by the degree of brake pedal depression in a conventional apparatus, the brake control does not harmonize with the driver's feel of how hard the brake pedal should be depressed. That is, the depressing force applied to the brake pedal is not always in proportion to the deceleration rate of the vehicle. Therefore, if the depressing force applied to the brake pedal is not released shortly before the vehicle completely stops, an uncomfortable jolt is experienced by the driver.